Optical device and mobile terminal

ABSTRACT

The present invention relates to a mobile terminal comprising a liquid lens including: a side wall part; a first and a second glass layer which cover one surface and the other surface of the side wall part, respectively, to form a receiving part; a plurality of electrode modules, each of which is positioned on the side wall part and includes a first and a second electrode; an insulation layer covering the first electrode; a nonpolar liquid filled in the receiving part; and a polar liquid which is separated from the polar liquid in layers, is filled in the receiving part, and is in contact with the second electrode, wherein a boundary surface between the nonpolar liquid and the polar liquid changes into a shape protruding toward the polar liquid as a voltage applied to the electrode modules increases, and a control part differently controls at least a part of the voltage applied to the plurality of electrode modules to adjust a position of a protrusion of the boundary surface.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the National Stage filing under 35 U.S.C. 371 ofInternational Application No. PCT/KR2018/012195, filed on Oct. 16, 2018,which claims the benefit of U.S. Provisional Application No. 62/643,771,filed on Mar. 16, 2018, the contents of which are all herebyincorporated by reference herein in their entirety.

TECHNICAL FIELD

The present disclosure relates to an optical device and a mobileterminal including the same.

BACKGROUND ART

Terminals may be generally classified as mobile/portable terminals orstationary terminals according to their mobility. Mobile terminals mayalso be classified as handheld terminals or vehicle mounted terminalsaccording to whether or not a user can directly carry the terminal.

Mobile terminals have become increasingly more functional. Examples ofsuch functions include data and voice communications, capturing imagesand video via a camera, recording audio, playing music files via aspeaker system, and displaying images and video on a display. Somemobile terminals include additional functionality which supports gameplaying, while other terminals are configured as multimedia players.More recently, mobile terminals have been configured to receivebroadcast and multicast signals which permit viewing of content such asvideos and television programs.

As such functions become more diversified, the mobile terminal maysupport more complicated functions such as capturing images or video,reproducing music or video files, playing games, receiving broadcastsignals, and the like. By comprehensively and collectively implementingsuch functions, the mobile terminal may be embodied in the form of amultimedia player or device.

As one of the functions of multimedia devices, photo-taking is a veryimportant function. Since the performance of a camera is related to theoverall performance of a mobile terminal, a camera capable of providinghigh-quality images and allowing miniaturization is an active researcharea. Recently, the camera function of a mobile terminal has reached thelevel of replacing a digital camera, and a small camera module may bemounted and utilized in various devices.

There is a need for an optical device capable of shooting in a varietyof situations, such as a camera capable of correcting hand tremors,taking a night view, or taking an ultra-close-up shot beyond the levelof shooting a general situation.

DISCLOSURE Technical Problem

An aspect of the present disclosure is to provide an optical device witha liquid lens capable of taking an ultra-close-up shot.

Technical Solution

A mobile terminal includes a case, an image sensor mounted in the case,a liquid lens located in front of the image sensor, a touch displaylocated on one surface of the case and outputting a preview image inputto the image sensor, and recognizing a touch input, and a controllerconfigured to control the image sensor, the liquid lens, and the touchdisplay. The liquid lens includes a sidewall, a first glass layer and asecond glass layer forming a container by covering one surface and theother surface of the sidewall, a plurality of electrode modules locatedon the sidewall and including an upper electrode and a lower electrode,an insulating layer covering the upper electrode, a non-polar liquidfilled in the container, and a polar liquid layered with the polarliquid, filled in the container, and contacting the lower electrode. Asa voltage applied to an electrode module increases, an interface betweenthe non-polar liquid and the polar liquid is changed to protrude towardthe polar liquid, and the controller is configured to adjust theposition of a protrusion of the interface by controlling at least a partof voltages applied to the plurality of electrode modules to bedifferent.

The plurality of electrode modules may be arranged along a periphery ofthe liquid lens, and the number of the plurality of electrode modulesmay be 8 or larger.

When a first zone of the preview image is selected, the controller maybe configured to control the electrode modules to protrude the interfaceof the polar liquid at a position corresponding to the first zone.

The controller may be configured to set a position at which a touchinput is sensed on the touch display as a first point.

Each of the voltages applied to the electrode modules may include afocus voltage V_(AF) corresponding to a focus which has been set and acompensation voltage ΔV compensating for shaking of the mobile terminal.

The first zone may include one of a plurality of zones divided from thepreview image, and the electrode modules may include at least two ofelectrode modules one to one corresponding to the plurality of zones.

The controller may be configured to control voltages of a plurality offirst electrode modules including an electrode module corresponding tothe first zone and an electrode module corresponding to a zone adjacentto the first zone to be lower than a voltage of a second electrodemodule corresponding to a second zone apart from the first zone in adiagonal direction.

A first voltage coefficient A for the compensation voltages of the firstelectrode modules may be larger than a second voltage coefficient C forthe second electrode module.

A third voltage coefficient B for a third electrode module other thanthe first electrode module and the second electrode module may besmaller than the first voltage coefficient A and smaller than the secondvoltage coefficient C.

A curvature center of the protrusion of the interface after the firstpoint is set may be different from a curvature center of the protrusionof the interface before the first point is set.

The controller may be configured to, upon sensing a command for storingthe preview image, obtain a plurality of preview images by adjusting thevoltages of the electrode modules to change the position of theprotrusion of the interface, and control an image obtained by combiningimages corresponding to the protrusion in the preview images to bestored.

The sidewall may have an inclined surface which becomes narrower towardthe first glass layer.

The non-polar liquid may have a larger refractive index than the polarliquid.

Advantageous Effects

A mobile terminal according to the present disclosure has the followingeffects.

An ultra-close-up shot may be taken with a desired part focused on.Therefore, a clear image of a user-desired part may be obtained.

A clearer ultra-close-up image may be obtained by solving the problem ofburring in an out-of-focus peripheral part of the image duringultra-close-up shooting.

An additional scope of applicability of the present disclosure willbecome apparent from the following detailed description. However, sincevarious changes and modifications within the spirit and scope of thepresent disclosure can be clearly understood by those skilled in theart, the detailed description and a specific embodiment such as apreferred embodiment of the present disclosure should be understood asgiven by way of example only.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a block diagram illustrating a mobile terminal related tothe present disclosure.

FIGS. 1 b and 1 c are conceptual diagrams illustrating an exemplarymobile terminal related to the present disclosure, viewed from differentdirections.

FIG. 2 is a conceptual sectional diagram illustrating an optical devicerelated to the present disclosure.

FIG. 3 is a diagram referred to for describing an electro-wettingtechnology related to the present disclosure.

FIG. 4 is a conceptual sectional view illustrating an electro-wettingliquid lens related to the present disclosure.

FIG. 5 is a diagram conceptually illustrating cross-sections of theelectro-wetting liquid lens of FIG. 4 according to voltages applied tothe electro-wetting liquid lens.

FIG. 6 a is a conceptual sectional view illustrating the electro-wettingliquid lens of FIG. 5(c), taken along line A-A′.

FIG. 6 b is a conceptual sectional view illustrating the electro-wettingliquid lens of FIG. 5(c), taken along line B-B′.

FIG. 7 is a driving block diagram illustrating an optical deviceincluding an electro-wetting liquid lens related to the presentdisclosure.

FIG. 8 is a sectional view illustrating the optical device related tothe present disclosure.

FIG. 9 is a diagram illustrating an electrode module in the opticaldevice related to the present disclosure.

FIG. 10 is a diagram referred to for describing an operation of theoptical device related to the present disclosure.

FIG. 11 is a diagram illustrating a preview image output to a touchdisplay in the mobile terminal related to the present disclosure.

FIGS. 12 to 15 are diagrams referred to for describing a method ofcontrolling a liquid lens in the mobile terminal related to the presentdisclosure.

BEST MODE

Description will now be given in detail according to exemplaryembodiments disclosed herein, with reference to the accompanyingdrawings. For the sake of brief description with reference to thedrawings, the same or equivalent components may be provided with thesame reference numbers, and description thereof will not be repeated. Ingeneral, a suffix such as “module” and “unit” may be used to refer toelements or components. Use of such a suffix herein is merely intendedto facilitate description of the specification, and the suffix itself isnot intended to give any special meaning or function. In the presentdisclosure, that which is well-known to one of ordinary skill in therelevant art has generally been omitted for the sake of brevity. Theaccompanying drawings are used to help easily understand varioustechnical features and it should be understood that the embodimentspresented herein are not limited by the accompanying drawings. As such,the present disclosure should be construed to extend to any alterations,equivalents and substitutes in addition to those which are particularlyset out in the accompanying drawings.

It will be understood that although the terms first, second, etc. may beused herein to describe various elements, these elements should not belimited by these terms. These terms are generally only used todistinguish one element from another.

It will be understood that when an element is referred to as being“connected with” another element, the element can be connected with theother element or intervening elements may also be present. In contrast,when an element is referred to as being “directly connected with”another element, there are no intervening elements present.

A singular representation may include a plural representation unless itrepresents a definitely different meaning from the context.

Terms such as “include” or “has” are used herein and should beunderstood that they are intended to indicate an existence of severalcomponents, functions or steps, disclosed in the specification, and itis also understood that greater or fewer components, functions, or stepsmay likewise be utilized.

Mobile terminals presented herein may be implemented using a variety ofdifferent types of terminals. Examples of such terminals includecellular phones, smart phones, user equipment, laptop computers, digitalbroadcast terminals, personal digital assistants (PDAs), portablemultimedia players (PMPs), navigators, portable computers (PCs), slatePCs, tablet PCs, ultra books, wearable devices (for example, smartwatches, smart glasses, head mounted displays (HMDs)), and the like.

Reference is now made to FIGS. 1 a to 1 c , where FIG. 1 a is a blockdiagram of a mobile terminal in accordance with the present disclosure,and FIGS. 1 b and 1 c are conceptual views of one example of the mobileterminal, viewed from different directions.

A mobile terminal 100 is shown having components such as a wirelesscommunication unit 110, an input unit 120, a sensing unit 140, an outputunit 150, an interface unit 160, a memory 170, a controller 180, and apower supply unit 190. It is understood that implementing all of theillustrated components is not a requirement, and that greater or fewercomponents may alternatively be implemented.

The wireless communication unit 110 typically includes one or moremodules which permit communications such as wireless communicationsbetween the mobile terminal 100 and a wireless communication system,communications between the mobile terminal 100 and another mobileterminal, communications between the mobile terminal 100 and an externalserver. Further, the wireless communication unit 110 typically includesone or more modules which connect the mobile terminal 100 to one or morenetworks.

To facilitate such communications, the wireless communication unit 110includes one or more of a broadcast receiving module 111, a mobilecommunication module 112, a wireless Internet module 113, a short-rangecommunication module 114, and a location information module 115.

The input unit 120 includes a camera 121 for obtaining images or video,a microphone 122, which is one type of audio input device for inputtingan audio signal, and a user input unit 123 (for example, a touch key, apush key, a mechanical key, a soft key, and the like) for allowing auser to input information. Data (for example, audio, video, image, andthe like) is obtained by the input unit 120 and may be analyzed andprocessed by controller 180 according to device parameters, usercommands, and combinations thereof.

The sensing unit 140 is typically implemented using one or more sensorsconfigured to sense internal information of the mobile terminal, thesurrounding environment of the mobile terminal, user information, andthe like. If desired, the sensing unit 140 may alternatively oradditionally include other types of sensors or devices, such as a touchsensor, an acceleration sensor, a magnetic sensor, a G-sensor, agyroscope sensor, a motion sensor, an RGB sensor, an infrared (IR)sensor, a finger scan sensor, a ultrasonic sensor, an optical sensor(for example, camera 121), a microphone 122, a battery gauge, anenvironment sensor (for example, a barometer, a hygrometer, athermometer, a radiation detection sensor, a thermal sensor, and a gassensor, among others), and a chemical sensor (for example, an electronicnose, a health care sensor, a biometric sensor, and the like), to name afew. The mobile terminal 100 may be configured to utilize informationobtained from sensing unit 140, and in particular, information obtainedfrom one or more sensors of the sensing unit 140, and combinationsthereof.

The output unit 150 is typically configured to output various types ofinformation, such as audio, video, tactile output, and the like. Theoutput unit 150 is shown having a display unit 151, an audio outputmodule 152, a haptic module 153, and an optical output module 154. Thedisplay unit 151 may have an inter-layered structure or an integratedstructure with a touch sensor in order to facilitate a touch screen. Thetouch screen may provide an output interface between the mobile terminal100 and a user, as well as function as the user input unit 123 whichprovides an input interface between the mobile terminal 100 and theuser.

The interface unit 160 serves as an interface with various types ofexternal devices that can be coupled to the mobile terminal 100. Theinterface unit 160, for example, may include any of wired or wirelessports, external power supply ports, wired or wireless data ports, memorycard ports, ports for connecting a device having an identificationmodule, audio input/output (I/O) ports, video I/O ports, earphone ports,and the like. In some cases, the mobile terminal 100 may performassorted control functions associated with a connected external device,in response to the external device being connected to the interface unit160.

The memory 170 is typically implemented to store data to support variousfunctions or features of the mobile terminal 100. For instance, thememory 170 may be configured to store application programs executed inthe mobile terminal 100, data or instructions for operations of themobile terminal 100, and the like. Some of these application programsmay be downloaded from an external server via wireless communication.Other application programs may be installed within the mobile terminal100 at time of manufacturing or shipping, which is typically the casefor basic functions of the mobile terminal 100 (for example, receiving acall, placing a call, receiving a message, sending a message, and thelike). It is common for application programs to be stored in the memory170, installed in the mobile terminal 100, and executed by thecontroller 180 to perform an operation (or function) for the mobileterminal 100.

The controller 180 typically functions to control overall operation ofthe mobile terminal 100, in addition to the operations associated withthe application programs. The controller 180 may provide or processinformation or functions appropriate for a user by processing signals,data, information and the like, which are input or output by the variouscomponents depicted in FIG. 1A, or activating application programsstored in the memory 170.

Further, the controller 180 controls some or all of the componentsillustrated in FIG. 1 a to execute an application program that has beenstored in the memory 170. Further, the controller 180 may operate atleast two of the components included in the mobile terminal 100 incombination to execute the application program.

The power supply unit 190 can be configured to receive external power orprovide internal power in order to supply appropriate power required foroperating elements and components included in the mobile terminal 100.The power supply unit 190 may include a battery, and the battery may beconfigured to be embedded in the terminal body, or configured to bedetachable from the terminal body.

At least some of the above-described components may operate incooperation with each other to implement operations, control, or controlmethod of the mobile terminal 100 according to various embodimentsdescribed below. Further, the operations, control, or control method ofthe mobile terminal may be performed in the mobile terminal by executingat least one application program stored in the memory 170.

Referring to FIGS. 1 b and 1 c , the mobile terminal 100 includes abar-type terminal body. However, the present disclosure is applicable tovarious structures including a watch type, a clip type, a glass type, afolder type having two or more bodies engaged with each other to berelatively movable, a flip type, a slide type, a swing type, a swiveltype, and so on, not limited to the bar type. While the presentdisclosure relates to a specific type of optical device, a descriptionof the specific type of optical device is generally applicable to othertypes of optical devices.

The terminal body may be understood conceptually as referring to themobile terminal 100 as at least one aggregate.

The mobile terminal 100 will generally include a case (for example,frame, housing, cover, and the like) forming the appearance of theterminal. In this embodiment, the case is formed using a front case 101and a rear case 102. Various electronic components are incorporated intoa space formed between the front case 101 and the rear case 102. Atleast one middle case may be additionally positioned between the frontcase 101 and the rear case 102.

The display unit 151 is shown located on the front side of the terminalbody to output information. As illustrated, a window 151 a of thedisplay unit 151 may be mounted to the front case 101 to form the frontsurface of the terminal body together with the front case 101.

In some embodiments, electronic components may also be mounted to therear case 102. Examples of such electronic components include adetachable battery 191, an identification module, a memory card, and thelike. Rear cover 103 is shown covering the electronic components, andthis cover may be detachably coupled to the rear case 102. Therefore,when the rear cover 103 is detached from the rear case 102, theelectronic components mounted to the rear case 102 are externallyexposed.

As illustrated, when the rear cover 103 is coupled to the rear case 102,a side surface of the rear case 102 is partially exposed. In some cases,upon the coupling, the rear case 102 may also be completely shielded bythe rear cover 103. In some embodiments, the rear cover 103 may includean opening for externally exposing a camera 121 b or an audio outputmodule 152 b.

The cases 101, 102, 103 may be formed by injection-molding syntheticresin or may be formed of a metal, for example, stainless steel (STS),aluminum (Al), titanium (Ti), or the like.

As an alternative to the example in which the plurality of cases form aninner space for accommodating components, the mobile terminal 100 may beconfigured such that one case forms the inner space. In this example, amobile terminal 100 having a uni-body is formed in such a manner thatsynthetic resin or metal extends from a side surface to a rear surface.

If desired, the mobile terminal 100 may include a waterproofing unit(not shown) for preventing introduction of water into the terminal body.For example, the waterproofing unit may include a waterproofing memberwhich is located between the window 151 a and the front case 101,between the front case 101 and the rear case 102, or between the rearcase 102 and the rear cover 103, to hermetically seal an inner spacewhen those cases are coupled.

The mobile terminal includes a display unit 151, a first and a secondaudio output modules 152 a/152 b, a proximity sensor 141, anillumination sensor 142, an optical output module 154, a first and asecond cameras 121 a/121 b, a first and a second manipulation units 123a/123 b, a microphone 122, interface unit 160 and the like.

It will be described for the mobile terminal as shown in FIGS. 1B and1C. The display unit 151, the first audio output module 152 a, theproximity sensor 141, an illumination sensor 142, the optical outputmodule 154, the first camera 121 a and the first manipulation unit 123 aare arranged in front surface of the terminal body, the secondmanipulation unit 123 b, the microphone 122 and interface unit 160 arearranged in side surface of the terminal body, and the second audiooutput modules 152 b, and the second camera 121 b are arranged in rearsurface of the terminal body.

However, it is to be understood that alternative arrangements arepossible and within the teachings of the instant disclosure. Somecomponents may be omitted or rearranged. For example, the firstmanipulation unit 123 a may be located on another surface of theterminal body, and the second audio output module 152 b may be locatedon the side surface of the terminal body.

The display unit 151 is generally configured to output informationprocessed in the mobile terminal 100. For example, the display unit 151may display execution screen information of an application programexecuting at the mobile terminal 100 or user interface (UI) and graphicuser interface (GUI) information in response to the execution screeninformation.

The display unit 151 outputs information processed in the mobileterminal 100. The display unit 151 may be implemented using one or moresuitable display devices. Examples of such suitable display devicesinclude a liquid crystal display (LCD), a thin film transistor-liquidcrystal display (TFT-LCD), an organic light emitting diode (OLED), aflexible display, a 3-dimensional (3D) display, an e-ink display, andcombinations thereof.

The display unit 151 may be implemented using two display devices, whichcan implement the same or different display technology. For instance, aplurality of the display units 151 may be arranged on one side, eitherspaced apart from each other, or these devices may be integrated, orthese devices may be arranged on different surfaces.

The display unit 151 may also include a touch sensor which senses atouch input received at the display unit. When a touch is input to thedisplay unit 151, the touch sensor may be configured to sense this touchand the controller 180, for example, may generate a control command orother signal corresponding to the touch. The content which is input inthe touching manner may be a text or numerical value, or a menu itemwhich can be indicated or designated in various modes.

The touch sensor may be configured in a form of a film having a touchpattern, disposed between the window 151 a and a display on a rearsurface of the window 151 a, or a metal wire which is patterned directlyon the rear surface of the window 151 a. Alternatively, the touch sensormay be integrally formed with the display. For example, the touch sensormay be disposed on a substrate of the display or within the display.

The display unit 151 may also form a touch screen together with thetouch sensor. Here, the touch screen may serve as the user input unit123 (see FIG. 1A). Therefore, the touch screen may replace at least someof the functions of the first manipulation unit 123 a.

The first audio output module 152 a may be implemented as a receiverthat provides a call sound to a user's ear. The second audio outputmodule 152 b may be implemented in the form of a loud speaker to outputalarm sounds, multimedia audio reproduction, and the like.

The window 151 a of the display unit 151 will typically include anaperture to permit audio generated by the first audio output module 152a to pass. One alternative is to allow audio to be released along anassembly gap between the structural bodies (for example, a gap betweenthe window 151 a and the front case 101). In this case, a holeindependently formed to output audio sounds may not be seen or isotherwise hidden in terms of appearance, thereby further simplifying theappearance and manufacturing of the mobile terminal 100.

The optical output module 154 can be configured to output light forindicating an event generation. Examples of such events include amessage reception, a call signal reception, a missed call, an alarm, aschedule notice, an email reception, information reception through anapplication, and the like. When a user has checked a generated event,the controller can control the optical output unit 154 to stop the lightoutput.

The first camera 121 a can process image frames such as still or movingimages obtained by the image sensor in a capture mode or a video callmode. The processed image frames can then be displayed on the displayunit 151 or stored in the memory 170.

The first and second manipulation units 123 a and 123 b are examples ofthe user input unit 123, which may be manipulated by a user to provideinput to the mobile terminal 100. The first and second manipulationunits 123 a and 123 b may also be commonly referred to as a manipulatingportion, and may employ any tactile method that allows the user toperform manipulation such as touch, push, scroll, or the like. The firstand second manipulation units 123 a and 123 b may also employ anynon-tactile method that allows the user to perform manipulation such asproximity touch, hovering, or the like.

FIG. 1 b illustrates the first manipulation unit 123 a as a touch key,but possible alternatives include a mechanical key, a push key, a touchkey, and combinations thereof.

Input received at the first and second manipulation units 123 a and 123b may be used in various ways. For example, the first manipulation unit123 a may be used by the user to provide an input to a menu, home key,cancel, search, or the like, and the second manipulation unit 123 b maybe used by the user to provide an input to control a volume level beingoutput from the first or second audio output modules 152 a or 152 b, toswitch to a touch recognition mode of the display unit 151, or the like.

As another example of the user input unit 123, a rear input unit (notshown) may be located on the rear surface of the terminal body. The rearinput unit can be manipulated by a user to provide input to the mobileterminal 100. The input may be used in a variety of different ways. Forexample, the rear input unit may be used by the user to provide an inputfor power on/off, start, end, scroll, control volume level being outputfrom the first or second audio output modules 152 a or 152 b, switch toa touch recognition mode of the display unit 151, and the like. The rearinput unit may be configured to permit touch input, a push input, orcombinations thereof.

The rear input unit may be located to overlap the display unit 151 ofthe front side in a thickness direction of the terminal body. As oneexample, the rear input unit may be located on an upper end portion ofthe rear side of the terminal body such that a user can easilymanipulate it using a forefinger when the user grabs the terminal bodywith one hand. Alternatively, the rear input unit can be positioned atmost any location of the rear side of the terminal body.

Embodiments that include the rear input unit may implement some or allof the functionality of the first manipulation unit 123 a in the rearinput unit. As such, in situations where the first manipulation unit 123a is omitted from the front side, the display unit 151 can have a largerscreen.

As a further alternative, the mobile terminal 100 may include a fingerscan sensor which scans a user's fingerprint. The controller 180 canthen use fingerprint information sensed by the finger scan sensor aspart of an authentication procedure. The finger scan sensor may also beinstalled in the display unit 151 or implemented in the user input unit123.

The microphone 122 is configured to receive a user's voice and othersounds. Microphones 122 may be provided at a plurality of positions suchthat they may receive stereo sounds.

The interface unit 160 may serve as a path allowing the mobile terminal100 to interface with external devices. For example, the interface unit160 may include one or more of a connection terminal for connecting toanother device (for example, an earphone, an external speaker, or thelike), a port for near field communication (for example, an InfraredData Association (IrDA) port, a Bluetooth port, a wireless LAN port, andthe like), or a power supply terminal for supplying power to the mobileterminal 100. The interface unit 160 may be implemented in the form of asocket for accommodating an external card, such as SubscriberIdentification Module (SIM), User Identity Module (UIM), or a memorycard for information storage.

The second camera 121 b is shown located at the rear side of theterminal body and includes an image capturing direction that issubstantially opposite to the image capturing direction of the firstcamera unit 121 a. If desired, second camera 121 a may alternatively belocated at other locations, or made to be moveable, in order to have adifferent image capturing direction from that which is shown.

The second camera 121 b can include a plurality of lenses arranged alongat least one line. The plurality of lenses may also be arranged in amatrix configuration. The cameras may be referred to as an “arraycamera.” When the second camera 121 b is implemented as an array camera,images may be captured in various manners using the plurality of lensesand images with better qualities.

As shown in FIG. 1 c , a flash 124 is shown adjacent to the secondcamera 121 b. When an image of a subject is captured with the camera 121b, the flash 124 may illuminate the subject.

As shown in FIG. 1 b , the second audio output module 152 b can belocated on the terminal body. The second audio output module 152 b mayimplement stereophonic sound functions in conjunction with the firstaudio output module 152 a, and may be also used for implementing aspeaker phone mode for call communication.

At least one antenna for wireless communication may be located on theterminal body. The antenna may be installed in the terminal body orformed by the case. For example, an antenna which configures a part ofthe broadcast receiving module 111 may be retractable into the terminalbody. Alternatively, an antenna may be formed using a film attached toan inner surface of the rear cover 103, or a case that includes aconductive material.

A power supply unit 190 for supplying power to the mobile terminal 100may include a battery 191, which is mounted in the terminal body ordetachably coupled to an outside of the terminal body.

The battery 191 may receive power via a power source cable connected tothe interface unit 160. Also, the battery 191 can be recharged in awireless manner using a wireless charger. Wireless charging may beimplemented by magnetic induction or electromagnetic resonance.

The rear cover 103 is shown coupled to the rear case 102 for shieldingthe battery 191, to prevent separation of the battery 191, and toprotect the battery 191 from an external impact or from foreignmaterial. When the battery 191 is detachable from the terminal body, therear case 103 may be detachably coupled to the rear case 102.

An accessory for protecting an appearance or assisting or extending thefunctions of the mobile terminal 100 can also be provided on the mobileterminal 100. As one example of an accessory, a cover or pouch forcovering or accommodating at least one surface of the mobile terminal100 may be provided. The cover or pouch may cooperate with the displayunit 151 to extend the function of the mobile terminal 100. Anotherexample of the accessory is a touch pen for assisting or extending atouch input to a touch screen.

FIG. 2 is a conceptual sectional diagram illustrating an optical device200 related to the present disclosure. The optical device 200illustrated in FIG. 2 is an example of the camera 121 included in themobile terminal 100 in FIG. 1 a.

The optical device 200 may include an aperture 211, at least one lens220, and an image sensor 230.

Light reflected or emitted from a subject 1 passes through at least onelens 220 and is refracted. The light which has passed and refracted fromthe at least one lens 220 reaches the image sensor 230.

The aperture 211 is located at a point in front of the at least one lens220 in an optical path and adjusts the amount of light reaching the atleast one lens 220 and the image sensor 230.

The image sensor 230 may include a red, green, blue (RGB) filter 231 forsensing RGB and a sensor array 232 for converting an optical signal intoan electrical signal.

The image sensor 230 may include a mask for phase difference detectionat the top or bottom of the RGB filter 231.

An image processor (not shown) may generate an RGB image based on theelectrical signal obtained from the image sensor 230.

A plurality of lenses 220 may be provided, and may have a fixed shapesuch as a glass lens or a plastic lens.

However, when the at least one lens 220 has a fixed shape like a glasslens or a plastic lens and thus a fixed refractive index, the at leastone lens 220 has limitations in executing functions such as autofocusing (AF) or image shake correction.

To solve the problem, the at least one lens 220 may be a liquid lens ina variable shape.

Liquid lenses may be classified into a membrane liquid lens deformed byexternal physical pressure and an electro-wetting liquid lens deformedby electrical interaction.

It may be more easily control the refractive index of theelectro-wetting liquid lens than that of the membrane liquid lens, inthat the former relies on external physical pressure and the latterrelies on external physical pressure, for deformation.

FIG. 3 is a diagram referred to for describing an electro-wettingtechnology related to the present disclosure. (a) illustrates a case inwhich a polar liquid such as water is positioned on a substrate with aninsulator deposited on a metal thereon. Water droplets are clustered ina circle due to surface tension, as indicated by a dotted line A. Whenelectricity is applied by connecting electrodes to the water dropletsand the metal, electric current flows through the water droplets,creating an attractive force between the water and the substrate. Thus,the water droplets form a gentle curve and spread on the substrate, asindicated by a solid line B.

When the voltage is equal to or higher than a predetermined level, thewater is electrolyzed. However, if the insulator is interposed between aconductive object and the water as illustrated in FIG. 3(a), watermolecules may not directly exchange electrons, so that decompositiondoes not take place. A liquid lens having a variable curvature may beimplemented by this electro-wetting technology.

For a conventional glass lens, the position of the lens is changed toadjust a focal length, whereas for a liquid lens, a focus may beadjusted by adjusting a voltage and thus changing the curvature of aliquid, which obviates the need for changing the position of the lens.The liquid lens may be implemented in a smaller space than theconventional glass lens and freely change its shape, compared to theglass lens fixed in its shape. Accordingly, the liquid lens allowsvarious controls.

As illustrated in FIG. 3(b), a liquid lens may be implemented by fillinga polar liquid (water) and a non-polar liquid (oil) in a containerincluding a substrate with a conductive object and an insulatordeposited on one surface thereof. In this embodiment, the interfacebetween the polar liquid and the non-polar liquid which have differentrefractive indices serves as the spherical surface of the lens, and theshape of the interface may be controlled by adjusting a voltage appliedto the polar solution and the metal.

In the embodiment of FIG. 3(b), the liquid lens is easier to controlbecause the interface between the polar liquid and the non-polar liquidmay be changed within a limited space than that of FIG. 3(a). The polarliquid and the non-polar solution are placed in the container, formingthe interface without being mixed, as illustrated in FIG. 3(b). When acurrent is applied to the polar liquid, the hydrophile property of thesubstrate becomes strong, and the interface between the polar liquid andthe non-polar liquid changes such that an area over which the substratecontacts the polar liquid increases. That is, the interface changes froma gentle shape indicated by a dotted line A to a round shape indicatedby a solid line B.

A convex lens may be implemented using a non-polar liquid having alarger refractive index than a polar liquid, and a concave lens may beimplemented using a polar liquid having a larger refractive index than anon-polar liquid.

FIG. 4 is a conceptual sectional view illustrating an electro-wettingliquid lens 400 related to the present disclosure.

The shape of the electro-wetting liquid lens 400 is adjusted bygenerating a potential difference and thus changing the electronconfiguration of a material.

The electro-wetting liquid lens 400 includes an upper electrode 411 anda lower electrode 412.

A current may flow through the upper electrode 411 and the lowerelectrode 412 to generate a potential difference. At least one of theupper electrode 411 or the lower electrode 412 may include a pluralityof terminals. Particularly, the lower electrode 412 may be provided as aplurality of terminals with respect to the cross-section of the liquidlens, which will be described later in detail.

As a current flows through the upper electrode 411 or the lowerelectrode 412, the electron configuration of a conductive solution 413is changed. The resulting interaction between electrons changes theshape of the conductive solution 413.

A liquid 414 may have a relatively specific refractive surface due tothe shape deformation of the conductive solution 413 and may function asa lens for refracting light in the electro-wetting liquid lens 400.

That is, as the shape of the liquid 414 is changed, a refractive index,a focal length, or a refraction direction is changed.

The shapes of the upper electrode 411 and the lower electrode 412 affectthe shapes of the conductive solution 413 and the liquid 414. Forexample, when the liquid 414 is provided in a separation space of thelower electrode 412 and the lower electrode 412 is inclined so that leftand right widths thereof become narrower toward the top, the largestforce is applied to the edges of the liquid 414, and thus the liquid 414is curved differently like a lens shape.

A non-conductive layer 415 is provided on the top surface of the lowerelectrode 412 to prevent a current from directly flowing between theconductive solution 413 and the lower electrode 412.

FIG. 5 is a diagram conceptually illustrating cross-sections of theelectro-wetting liquid lens 400 of FIG. 4 according to voltages appliedto the electro-wetting liquid lens 400.

As described above, the shape of the liquid 414 changes according to thepotential difference between the upper electrode 411 and the lowerelectrode 412.

In FIGS. 5(a), 5(b) and 5(c), the potential difference between the upperelectrode 411 and the lower electrode 412 increases sequentially. Theliquid lens 414 changes in shape to switch from the properties of aconcave lens to the properties of a convex lens in the order of FIG.5(a) to FIG. 5(c).

That is, as the potential difference between the upper electrode 411 andthe lower electrode 412 increases, the diopter of the electro-wettingliquid lens 400 increases. This means that when the liquid 414 is in thestate of a concave lens, the lens curvature decreases as the potentialdifference increases, and when the liquid 414 is in the state of aconvex lens, the lens curvature increases as the potential differenceincreases.

While the liquid lens 414 is shown in FIG. 5 as having a symmetriccurved surface or flat surface, the liquid lens 414 may also have anasymmetric curved surface, not limited to the symmetric curved surfaceor flat surface.

When the liquid lens 400 has an asymmetric curved surface, the travelingdirection of light may deviate from a central axis.

However, the curvature or diopter of the electro-wetting liquid lens 400may change according to not only a potential difference, but also apulse width applied to each of the electrodes 411 and 412 or thedifference between pulse applying timings.

FIG. 6 a is a conceptual sectional view illustrating the electro-wettingliquid lens of FIG. 5(c), taken along line A-A′.

The lower electrode 412 may include a plurality of electrodes 412 a, 412b, 412 c, and 412 d. The plurality of electrodes 412 a, 412 b, 412 c,and 412 d may be sequentially arranged on the outer circumferentialsurface of the conductive solution 413 or the liquid 414. That is, theplurality of electrodes 412 a, 412 b, 412 c, and 412 d may besequentially arranged in the shape of a hollow tube.

The use of the plurality of electrodes 412 a, 412 b, 412 c, and 412 dimplies that different voltages may be applied, and thus the shape ofthe liquid lens may vary based on the above-described principle. Inother words, different potential differences are applied to theplurality of electrodes 412 a, 412 b, 412 c, and 412 d. A high potentialdifference is formed at a location where the boundary of the liquid 414is low, and a low potential difference is formed at a location where theboundary of the liquid 414 is high.

When the lower electrode 412 includes a plurality of electrodes, as manynon-conductive layers 415 as the number of the lower electrodes 412 maybe provided.

FIG. 6 b is a conceptual sectional view illustrating the electro-wettingliquid lens of FIG. 5(c), taken along line B-B′.

Unlike the lower electrode 412, the upper electrode 411 may be providedas a single electrode that is not divided. The lower electrode 412serves as a counterpart to the plurality of lower electrodes 412 a, 412b, 412 c, and 412 d forming different potential differences.

FIG. 7 is an exemplary driving block diagram illustrating the opticaldevice 200 including the electro-wetting liquid lens 400 related to thepresent disclosure.

The optical device 200 related to the present disclosure may include alens curvature changing device 500 that changes the curvature of theelectro-wetting liquid lens 400, an image sensor 530 that converts lightfrom the electro-wetting liquid lens 400 into an electric signal, and animage processor 540 that performs image processing based on theelectrical signal from the image sensor 530.

The optical device 200 related to the present disclosure may furtherinclude a gyro sensor 550.

The image processor 540 may output focus information about an image, andthe gyro sensor 915 may output optical image stabilization (OIS)information.

The lens curvature changing device 500 according to an embodiment of thepresent disclosure may include a lens controller 510, a diopter drivingunit 520, and a power supply 560.

The lens controller 510 sets a target diopter value for theelectro-wetting liquid lens 400 based on the focus information receivedfrom the image processor 540, and specifies a voltage value or a pulsewidth corresponding to the diopter value, so that the diopter drivingunit 520 may apply the voltage to the electro-wetting liquid lens 400.

Specifically, in operation of the lens curvature changing device 500,the lens controller 510 may output a pulse width variable signal V inresponse to a target diopter value, and the diopter driving unit 520 mayoutput a corresponding voltage to the lower electrode and the upperelectrode of the electro-wetting liquid lens 400 based on the pulsewidth variable signal V and a voltage Vx from the power supply unit 560.

This scheme of applying a voltage corresponding to a target diopter ofthe electro-wetting liquid lens 400 may be defined as an open loopsystem. A shortcoming with the scheme is that it may not be sensedwhether the desired diopter value has been reached.

When the curvature of the electro-wetting liquid lens 400 needs to bechanged to prevent shaking, the lens curvature variable device 500 ofFIG. 7 may have difficulty in accurately changing the curvature becausea curvature is not sensed.

FIG. 8 illustrates a cross-section of the optical device 200 related tothe present disclosure. Referring to FIG. 8(a), the optical device ofthe present disclosure includes the image sensor 230 and the liquid lens400. The image sensor 230 is a device that converts optical informationto digital information. For the image sensor 230, an ultra-smallsemiconductor such as a metal oxide semiconductor (MOS) or a chargecoupled device (CCD) may be used. A lens is located in front of theimage sensor 230 so that an accurate image is formed on the image sensor230, and the liquid lens 400 is used in the present disclosure.

The liquid lens 400 of the present disclosure includes the polar liquid413 and the non-polar liquid 414 filled in a container includingsidewalls, a first glass layer 416, and a second glass layer 417. Thepolar liquid 413 and the non-polar liquid 414 are not mixed and aredivided into layers. The one pair of electrodes 411 and 412 may belocated on the left and right sidewalls. The upper electrode 411 iscovered with the insulating layer 415 so that it does not directlycontact the polar liquid 413 or the non-polar liquid 414, whereas thelower electrode 412 contacts the polar liquid 413. When power issupplied to the upper electrode 411 and the lower electrode 412, chargeis concentrated between the upper electrode 411 and the polar liquid 413with the insulating layer 415 therebetween, as illustrated in FIG. 8(a).In order to increase an area over which the insulating layer 415contacts the polar liquid 413, the interface between the polar liquid413 and the non-polar liquid 414 is changed to be convex, as illustratedin FIG. 8(b).

The sidewalls of the present disclosure may have tapered surfaces thatare narrower toward the image sensor 230 at positions corresponding tothe lower electrode 412 and the insulating layer 415. As the liquid lens400 of the present disclosure is a convex lens which collects light andtransmit the collected light to the image sensor, the inclined sidewallsfacilitate adjustment of the curvature of the interface, compared tovertical sidewalls. Since the contact area between the polar liquid 413and the insulating layer 415 may be increased through the inclinedsurface, it is easy to change the curvature of the interface between thepolar liquid 413 and the non-polar liquid 414.

In order to adjust the curvature of the interface, only one electrodemodule 220 including the upper electrode 411 and the lower electrode 412is required. However, the present disclosure provides the liquid lens400 which may change an optical axis formed by the curved surface of theinterface between the polar liquid 413 and the non-polar liquid 414.

FIG. 9 is a diagram illustrating an electrode module 420 of the opticaldevice 200 according to the present disclosure. A plurality of electrodemodules 421 to 428 may be provided, which are arranged around theperiphery of the liquid lens 400 to change the optical axis of theliquid lens 400. Each of the electrode modules 421 to 428 includes theupper electrode 411 and the lower electrode 412 connected to a cathodeand an anode of the power supply unit 190, respectively.

While the electrode modules 420 are shown in FIG. 9 as arranged at equalintervals, the interval between the electrode modules 420 may not beconstant. Although eight electrode modules 420 are shown in FIG. 9 , thenumber of electrode modules 420 may be equal to or larger than 8.

As illustrated in FIG. 9 , the electrode modules 420 are located onsidewalls having inclined surfaces, and portions corresponding to thefirst glass are opened. For the convenience of description, theelectrode modules 420 will be referred to as a first node 421 to aneighth node 228 in a clockwise direction.

As illustrated in FIG. 8 , in order to change a focus by changing thecurvature of the liquid lens 400 without changing the position of theoptical axis of the interface, the same voltage V_(AF) may be applied(ΔV₁ to ΔV₈ are 0) as voltages V₁ to V₈ for the electrode modules 420.As the voltage increases, the interface of the liquid lens 400 becomesmore convex and the focal length becomes shorter.

The present disclosure is characterized in that the optical axis oflight incident on the liquid lens 400 is changed by using the pluralityof electrode modules 420. The optical axis is a path of light thatbecomes an image formation center and corresponds to a focal position.To adjust the optical axis, the shape of the interface between the polarsolution and the non-polar solution may be changed by applying adifferent voltage to each of the electrode modules 421 to 428. Thevoltage applied to each electrode module may change the shape of theliquid lens interface by adjusting the compensation voltages ΔV₁ to ΔV₈which are increased or decreased based on the reference voltage V_(AF),when the optical axis is centered.

FIG. 10 is a diagram referred to for describing operation of a camerarelated to the present disclosure. When the mobile terminal 100 isshaken, the mobile terminal 100 of the present disclosure may adjust ΔV₁to ΔV₈ to change the shape of the lens in correspondence with theshaking of the mobile terminal 100, so that a clear image is obtained bycompensating for the shaking of the mobile terminal 100. This techniqueis called optical image stabilization (OIS). Conventionally, the lens isoptically shifted or the image recognized by the image sensor 230 iselectronically shifted, to correct shaking. In contrast, the shape ofthe interface of the liquid lens 400 may be adjusted in the presentdisclosure.

Since the interface of the liquid lens should be inclined in a mannerthat compensates for shaking of the mobile terminal, the compensationvoltages of the electrode modules 420 positioned in a diagonal directionwith respect to the center may be complementary voltages. For example,ΔV₅ diagonal to ΔV₁ may have a negative value of ΔV₁, and ΔV₇ diagonalto ΔV₃ may have a negative value of ΔV₃.

A motion of the mobile terminal 100 may be divided into an x-axiscomponent θx and a y-axis component θy. When the electrode modules 420are divided on an x-y plane, the first node 421 and the eighth node 428in a first zone Zone_1 are located in the second quadrant and have −θxand +θy components, whereas the second node 422 and the third node 423in a second zone, Zone_2 are located in the first quadrant and have +θxand +θy components.

The fourth node 424 and the fifth node 425 in a third zone Zone_3 arelocated in the fourth quadrant and have +θx and −θy components, whereasthe sixth node 426 and the seventh node 427 in a fourth zone, Zone 4 arelocated in the third quadrant and have −θx and −θy components.

Accordingly, the first node 421 and the eighth node 228 located in thefirst zone, Z_1 may add a K(−θx+θy) value to the voltage value V_(AF)set for a corresponding focal length. K is a compensation voltagecoefficient, which may be determined by factors such as the curvature ofthe liquid lens 400 and the distance between the image sensor 230 andthe liquid lens 400.

The fourth node 224 and the fifth node 425 located in the third zone,Z_3 may add a K(θx-θy) value to the voltage value V_(AF). That is, thevoltage of each electrode module 420 may be adjusted so thatΔV_(4, 5)=−ΔV_(8,1).

The voltages ΔV₂ and ΔV₃ applied to the electrode modules 420 in thesecond zone Z_2 may also have the negative values of the voltages ΔV₆and ΔV₇ applied to the electrode modules 420 in the fourth zone Z_4.When the voltages are adjusted in this manner, the liquid lens 400 maycompensate for shaking of the mobile terminal, so that a clear image maybe obtained in the image sensor 230.

The use of the liquid lens 400 allows free changing of the curvature.With the resulting increased focus length control range, anultra-close-up shot may be taken. FIG. 11 is a diagram illustrating apreview image output on the touch display 151 of the mobile terminal 100related to the present disclosure. The preview image is obtained duringultra-close-up shooting.

The image becomes blurry from the center toward the edges because thecenter part is in good focus, but the edges experience distortion andthus are out of focus. Particularly as illustrated in FIG. 11 , thecorners are out of focus because they are far from the center in focus.The preview image output on the touch display 151 may be divided intofour zones corresponding to the first to fourth zones of the liquid lens400.

Since the electrodes of FIG. 9 are viewed from the front of the liquidlens 400, the top right zone of the preview image, that is, the zone ofthe first quadrant corresponds to the first zone of the liquid lens 400.The top left zone of the preview image corresponds to the second zone ofthe liquid lens 400. The bottom right zone of the preview imagecorresponds to the third zone of the liquid lens 400. The top left zoneof the preview image corresponds to the fourth zone of the liquid lens400.

As illustrated in FIG. 11 , when one of the zones of the touch display151 is selected to obtain an image clear at positions other than thecenter, the optical axis of the liquid lens 400 may be moved to focus onthe corresponding positions in the present disclosure. An image clear ina part corresponding to the selected zone may be obtained without movingthe mobile terminal 100.

When a zone for which the optical axis is to be moved is selected, thevoltage of the electrode module 420 adjacent to the zone may beincreased and the voltage of portions spaced from the zone may bedecreased, to move the optical axis. The position of the optical axismay be adjusted by differentiating the voltage coefficients A, B, and Cof the compensation voltages ΔV that compensate the voltages of theelectrode modules 420.

In the case of ultra-close-up shooting, it is difficult to obtain animage with clear edges. Accordingly, it is important to maintain aconstant curvature near the optical axis rather than a curvature at anouter portion. The voltage applied to an adjacent electrode module 420on which the optical axis is located may be controlled to be constant sothat the optical axis moves while the curvature near the optical axis ofthe liquid lens 400 illustrated in FIG. 8B is maintained.

FIGS. 12 to 15 are diagrams referred to for describing a method ofcontrolling the liquid lens 400 of the mobile terminal 100 related tothe present disclosure. FIG. 7 illustrates a voltage applied to eachelectrode module 420 when the first zone is selected, and FIG. 8illustrates a voltage applied to each electrode module 420 when thesecond zone is selected. FIG. 9 illustrates a voltage applied to eachelectrode module 420 when the third zone is selected, and FIG. 10illustrates a voltage applied to each electrode module 420 when thefourth zone is selected.

A position to be focused, that is, a zone to which the optical axis isto be moved may be selected by voice recognition or a user touch on thetouch display 151. In this case, the mobile terminal 100 may be shakenby the user's hand tremors. When the user touches and selects a zone towhich the optical axis of the liquid lens 400 is to be moved, the mobileterminal 100 may be shaken. Particularly in the case of ultra-close-upshooting, even a slight vibration leads to out-of-focus. Therefore, aclear image may be obtained only by compensating for the shaking.

Therefore, as illustrated in FIGS. 12 to 14 , when the mobile terminal100 moves by θ in FIG. 10 , a compensation factor K(±θx±θy) may beincluded in the formula of calculating a voltage applied to eachelectrode module 420. That is, focus shift is performed simultaneouslywith shake correction in the present disclosure.

Referring to FIG. 12 , when eight electrode modules 420 are included,compensation voltages ΔV₁, ΔV₂, ΔV₇, and ΔV₈ for voltages applied tofour adjacent electrode modules 421, 422, 427, and 428 adjacent to aselected zone (first zone) may be calculated by multiplying a largestvoltage coefficient A, whereas compensation voltages ΔV₄ and ΔV₅ forvoltages applied to two electrode modules 424 and 425 farthest from thefirst zone may be calculated by multiplying a smallest voltagecoefficient C. Compensation voltages ΔV₃ and ΔV₆ for voltages applied tothe remaining electrode modules 423 and 226 may be calculated bymultiplying a voltage coefficient B smaller than A and larger than C.

In FIG. 13 , the compensation voltages ΔV₁ to ΔV₈ may be calculated byassigning weights to the electrode modules 421, 422, 423, and 224adjacent to the second zone, and in FIG. 14 , the compensation voltagesΔV₁ to ΔV₈ may be calculated by assigning weights to the electrodemodules 425, 426, 427, and 428 adjacent to the third zone. In FIG. 13 ,the compensation voltages ΔV₁ to ΔV₈ may be calculated by assigningweights to the electrode modules 423, 424, 425, and 426 adjacent to thefourth zone.

Even if the optical axis moves in this manner, adjustment may beperformed so that the curvature near the optical axis is maintained,only when at least two electrodes are arranged per zone to which theoptical axis is to be moved. Therefore, as many electrode modules as ormore electrode modules than the double of the number of divided zonesmay be included.

When the optical axis moves, a position at which an image is accuratelyformed is changed. Therefore, a clear image may be obtained by focusingon a desired part without moving the mobile terminal 100 duringultra-close-up shooting.

Further, as illustrated in FIGS. 12 to 15 , images each having a zonefocused may be obtained and synthesized into a whole clear image. Aclearer ultra-close-up image may be obtained by solving the problem ofblurring in out-of-focus edges of an image during ultra-close-upshooting.

Those skilled in the art will appreciate that the present disclosure maybe carried out in other specific ways than those set forth hereinwithout departing from the spirit and essential characteristics of thepresent disclosure. The above embodiments are therefore to be construedin all aspects as illustrative and not restrictive. The scope of thedisclosure should be determined by the appended claims and their legalequivalents, not by the above description, and all changes coming withinthe meaning and equivalency range of the appended claims are intended tobe embraced therein.

The invention claimed is:
 1. A mobile terminal comprising: a case; animage sensor mounted in the case; a liquid lens located in front of theimage sensor; a touch display located on one surface of the case andoutputting a preview image input to the image sensor, and recognizing atouch input; and a controller configured to control the image sensor,the liquid lens, and the touch display, wherein the liquid lenscomprises: a sidewall; a first glass layer and a second glass layerforming a container by covering one surface and the other surface of thesidewall; a plurality of electrode modules located on the sidewall andincluding an upper electrode and a lower electrode; an insulating layercovering the upper electrode; a non-polar liquid filled in thecontainer; and a polar liquid layered with the polar liquid, filled inthe container, and contacting the lower electrode, wherein as a voltageapplied to an electrode module increases, an interface between thenon-polar liquid and the polar liquid is changed to protrude toward thepolar liquid, and the controller is configured to adjust the position ofa protrusion of the interface by controlling at least a part of voltagesapplied to the plurality of electrode modules to be different, whereinwhen a first zone of the preview image is selected, the controller isfurther configured to control the plurality of electrode modules toprotrude the interface of the polar liquid at a position correspondingto the first zone, and wherein the controller is further configured toset a position at which a touch input is sensed on the touch display asa first point.
 2. The mobile terminal according to claim 1, wherein theplurality of electrode modules are arranged along a periphery of theliquid lens, and the number of the plurality of electrode modules is 8or larger.
 3. The mobile terminal according to claim 1, wherein each ofthe voltages applied to the electrode modules includes a focus voltageV_(AF) corresponding to a focus which has been set and a compensationvoltage ΔV compensating for shaking of the mobile terminal.
 4. Themobile terminal according to claim 3, wherein the first zone includesone of a plurality of zones divided from the preview image, and theelectrode modules include at least two of electrode modules one to onecorresponding to the plurality of zones.
 5. The mobile terminalaccording to claim 4, wherein the controller is configured to controlvoltages of a plurality of first electrode modules including anelectrode module corresponding to the first zone and an electrode modulecorresponding to a zone adjacent to the first zone to be lower than avoltage of a second electrode module corresponding to a second zoneapart from the first zone in a diagonal direction.
 6. The mobileterminal according to claim 5, wherein a first voltage coefficient A forthe compensation voltages of the first electrode modules is larger thana second voltage coefficient C for the second electrode module.
 7. Themobile terminal according to claim 6, wherein a third voltagecoefficient B for a third electrode module other than the firstelectrode module and the second electrode module is smaller than thefirst voltage coefficient A and smaller than the second voltagecoefficient C.
 8. The mobile terminal according to claim 1, wherein acurvature center of the protrusion of the interface after the firstpoint is set is different from a curvature center of the protrusion ofthe interface before the first point is set.
 9. The mobile terminalaccording to claim 1, wherein the controller is configured to, uponsensing a command for storing the preview image, obtain a plurality ofpreview images by adjusting the voltages of the electrode modules tochange the position of the protrusion of the interface, and control animage obtained by combining images corresponding to the protrusion inthe preview images to be stored.
 10. The mobile terminal according toclaim 1, wherein the sidewall has an inclined surface which becomesnarrower toward the first glass layer.
 11. The mobile terminal accordingto claim 1, wherein the non-polar liquid has a larger refractive indexthan the polar liquid.